diff --git a/core/modules/book/lib/Drupal/book/BookManager.php b/core/modules/book/lib/Drupal/book/BookManager.php
index 144cc94..abd1820 100644
--- a/core/modules/book/lib/Drupal/book/BookManager.php
+++ b/core/modules/book/lib/Drupal/book/BookManager.php
@@ -68,7 +68,7 @@ protected function loadBooks() {
     $nids = $this->database->query("SELECT DISTINCT(bid) FROM {book}")->fetchCol();
 
     if ($nids) {
-      $query = db_select('book', 'b', array('fetch' => \PDO::FETCH_ASSOC));
+      $query = $this->database->select('book', 'b', array('fetch' => \PDO::FETCH_ASSOC));
       $query->join('menu_links', 'ml', 'b.mlid = ml.mlid');
       $query->fields('b');
       $query->fields('ml');
diff --git a/core/modules/comment/comment.admin.inc b/core/modules/comment/comment.admin.inc
index cb62a60..84e61f6 100644
--- a/core/modules/comment/comment.admin.inc
+++ b/core/modules/comment/comment.admin.inc
@@ -91,15 +91,16 @@ function comment_admin_overview($form, &$form_state, $arg) {
     ->orderByHeader($header)
     ->execute();
 
+  $nids = array();
   $cids = array();
 
   // We collect a sorted list of node_titles during the query to attach to the
   // comments later.
   foreach ($result as $row) {
-    $node = node_load($row->nid);
+    $nids[] = $row->nid;
     $cids[] = $row->cid;
-    $node_titles[] = $node->label();
   }
+  $node = node_load_multiple($nids);
   $comments = comment_load_multiple($cids);
 
   // Build a table listing the appropriate comments.
@@ -109,7 +110,7 @@ function comment_admin_overview($form, &$form_state, $arg) {
   foreach ($comments as $comment) {
     // Remove the first node title from the node_titles array and attach to
     // the comment.
-    $node_title = array_shift($node_titles);
+    $node_title = $comment->nid->entity->label();
     $options[$comment->id()] = array(
       'subject' => array(
         'data' => array(
diff --git a/core/modules/comment/comment.install b/core/modules/comment/comment.install
index 57b0c3b..9640304 100644
--- a/core/modules/comment/comment.install
+++ b/core/modules/comment/comment.install
@@ -37,9 +37,8 @@ function comment_uninstall() {
  */
 function comment_enable() {
   // Insert records into the node_comment_statistics for nodes that are missing.
-  // TODO Add support for multilingual properties.
   $query = db_select('node_field_data', 'n');
-  $query->leftJoin('node_comment_statistics', 'ncs', 'ncs.nid = n.nid');
+  $query->leftJoin('node_comment_statistics', 'ncs', 'ncs.nid = n.nid AND n.default_langcode = 1');
   $query->addField('n', 'created', 'last_comment_timestamp');
   $query->addField('n', 'uid', 'last_comment_uid');
   $query->addField('n', 'nid');
diff --git a/core/modules/comment/comment.module b/core/modules/comment/comment.module
index 32f89ca..795fc65 100644
--- a/core/modules/comment/comment.module
+++ b/core/modules/comment/comment.module
@@ -466,6 +466,9 @@ function comment_get_recent($number = 10) {
     ->fields('c')
     ->condition('c.status', COMMENT_PUBLISHED)
     ->condition('n.status', NODE_PUBLISHED)
+    // @todo This should be actually filtering on the desired node status field
+    //   language and just fall back to the default language.
+    ->condition('n.default_langcode', 1)
     ->orderBy('c.created', 'DESC')
     // Additionally order by cid to ensure that comments with the same timestamp
     // are returned in the exact order posted.
diff --git a/core/modules/forum/forum.module b/core/modules/forum/forum.module
index f142da5..c234645 100644
--- a/core/modules/forum/forum.module
+++ b/core/modules/forum/forum.module
@@ -749,6 +749,9 @@ function forum_forum_load($tid = NULL) {
     $counts = $query
       ->fields('f', array('tid'))
       ->condition('n.status', 1)
+      // @todo This should be actually filtering on the desired node status
+      //   field language and just fall back to the default language.
+      ->condition('n.default_langcode', 1)
       ->groupBy('tid')
       ->addTag('node_access')
       ->execute()
@@ -781,6 +784,9 @@ function forum_forum_load($tid = NULL) {
     $topic = $query
       ->fields('ncs', array('last_comment_timestamp', 'last_comment_uid'))
       ->condition('n.status', 1)
+      // @todo This should be actually filtering on the desired node status
+      //   field language and just fall back to the default language.
+      ->condition('n.default_langcode', 1)
       ->orderBy('last_comment_timestamp', 'DESC')
       ->range(0, 1)
       ->addTag('node_access')
@@ -825,6 +831,9 @@ function _forum_topics_unread($term, $uid) {
   $query->addExpression('COUNT(n.nid)', 'count');
   return $query
     ->condition('status', 1)
+    // @todo This should be actually filtering on the desired node status field
+    //   language and just fall back to the default language.
+    ->condition('n.default_langcode', 1)
     ->condition('n.created', HISTORY_READ_LIMIT, '>')
     ->isNull('h.nid')
     ->addTag('node_access')
@@ -913,7 +922,9 @@ function forum_get_topics($tid, $sortby, $forum_per_page) {
       ->orderBy('f.sticky', 'DESC')
       ->orderByHeader($forum_topic_list_header)
       ->condition('n.nid', $nids)
-      ->groupBy('n.nid');
+      // @todo This should be actually filtering on the desired node status
+      //   field language and just fall back to the default language.
+      ->condition('n.default_langcode', 1);
 
     $result = array();
     foreach ($query->execute() as $row) {
@@ -1293,7 +1304,9 @@ function _forum_update_forum_index($nid) {
   }
   else {
     // Comments do not exist.
-    $node = db_query('SELECT uid, created FROM {node_field_data} WHERE nid = :nid LIMIT 1', array(':nid' => $nid))->fetchObject();
+    // @todo This should be actually filtering on the desired node status field
+    //   language and just fall back to the default language.
+    $node = db_query('SELECT uid, created FROM {node_field_data} WHERE nid = :nid AND default_langcode = 1', array(':nid' => $nid))->fetchObject();
     db_update('forum_index')
       ->fields( array(
         'comment_count' => 0,